U.S. patent application number 10/020321 was filed with the patent office on 2003-06-12 for method for buffer crane operation in cargo container handling.
This patent application is currently assigned to PACECO CORP.. Invention is credited to Huang, Sun Huan, Takehara, Toru, Tam, Philip Alexander, Vosskamp, Hans G..
Application Number | 20030106869 10/020321 |
Document ID | / |
Family ID | 21797959 |
Filed Date | 2003-06-12 |
United States Patent
Application |
20030106869 |
Kind Code |
A1 |
Takehara, Toru ; et
al. |
June 12, 2003 |
Method for buffer crane operation in cargo container handling
Abstract
A method for buffer crane operation for supplementing a quay
crane operation and formed to operate thereunder with a landing
deck for supporting a multiple of cargo containers in buffer
operation above dockside cargo transport operations and for moving
cargo containers therebetween by means of a dedicated crane engaged
with said landing deck.
Inventors: |
Takehara, Toru; (San Mateo,
CA) ; Tam, Philip Alexander; (Emeryville, CA)
; Huang, Sun Huan; (Fremont, CA) ; Vosskamp, Hans
G.; (San Mateo, CA) |
Correspondence
Address: |
BRUCE & MCCOY
ONE KAISER PLAZA
STE. 2360
OAKLAND
CA
94612
US
|
Assignee: |
PACECO CORP.
|
Family ID: |
21797959 |
Appl. No.: |
10/020321 |
Filed: |
December 11, 2001 |
Current U.S.
Class: |
212/270 ;
212/312 |
Current CPC
Class: |
B66C 19/002 20130101;
B65G 63/004 20130101 |
Class at
Publication: |
212/270 ;
212/312 |
International
Class: |
B66C 019/00; B66C
005/02 |
Claims
We claim:
1. A method for dockside buffer crane cargo container handling in
combination with a quay crane, the steps comprising providing an
independently movable platform having a multiplicity of cargo
container landing positions disposed thereon and a dedicated crane
engaged with said platform arranged to transfer containers between
said platform and cargo container transporters located alongside or
below said platform, positioning said platform dockside under said
quay crane, moving containers by said quay crane between said
landing positions on said platform and shipboard cells of a
dockside berthed ship, and moving containers by said dedicated
crane between said platform landing positions and said cargo
container transporters concurrently with the movement of containers
by said quay crane.
2. The method of claim 1 including the step of performing interbox
connector installation and removal operations while containers are
temporarily positioned on said platform.
3. The method of claim 1 including the step of independently moving
said platform to each operational position of said quay crane on
said dock as said quay crane moves along said dock to unload the
length of a container ship.
4. The method of claim 1 wherein said dedicated crane is a slewing
jib crane.
5. The method of claim 1 wherein said dedicated crane is a bridge
crane.
6. The method of claim 1 wherein said dedicated crane is a straddle
crane.
7. A method for dockside buffer crane cargo container handling in
combination with a quay crane, the steps comprising providing an
independently movable platform having a multiplicity of cargo
container landing positions disposed thereon and a dedicated crane
engaged with said platform arranged to transfer containers between
said platform and cargo container transporters located alongside or
below said platform, positioning said platform dockside under said
quay crane, moving containers by said quay crane between said
landing positions on said platform and shipboard cells of a
dockside berthed ship, moving containers by said dedicated crane
between said platform landing positions and said cargo container
transporters concurrently with the movement of containers by said
quay crane, performing portions of said dedicated crane container
handling by automated control, performing interbox connector
installation and removal operations while containers are
temporarily positioned on said platform, and independently moving
said platform to each operational position of said quay crane on
said dock as said quay crane moves along said dock to unload the
length of a container ship.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. patent applications Ser.
Nos. ______ filed concurrently herewith.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a supplemental
sub-operation for cargo container handling by gantry cranes for
improving the efficiency of the container handling cycle time. More
particularly, it relates to a new method of operation for dockside
quay cranes. Specifically, it relates to the supplemental operation
of a buffer crane which functions in conjunction with cargo
container handling gantry cranes.
[0004] 2. Description of the Prior Art
[0005] The utilization of various types of cargo container handling
gantry cranes or quay cranes for the purpose of increasing the
speed of loading and unloading of cargo container transport ships
is well-established in the prior art. However, despite the numerous
designs, structures, and methods of operation disclosed by the
prior art, which have been developed for the accomplishment of the
specific objectives, purposes, and requirements of cargo container
handling, the apparatus and methods which have heretofore been
devised and utilized consist basically of familiar, expected, and
obvious configurations, combinations, and arrangements of
well-known machinery operations. This will become apparent from the
following consideration of the closest known and relevant prior
art.
[0006] Shipping companies wish to reduce the time a ship spends in
port involved in berthing operations in order to increase the
efficiency of each vessel. Increasing the productivity of berthing
operations allows ships to be loaded and unloaded faster, thereby
effectively reducing the ship's down time. Efforts are continuously
being made to further this objective. The present invention is a
significant advancement in these efforts.
[0007] Reference is made to FIG. 1 of the drawings which shows a
typical dockside berthing operation for a ship. The primary
container handling equipment is comprised of one or more quay
cranes 11 which extend outboard from the dock's edge 13 across the
beam of a ship 15. Cargo containers 17 which have been unloaded or
are to be loaded are temporarily stored in a stacking yard 19
proximate to the ship's loading berths. The berthing operations
under specific consideration involve the transport of containers
between a container ship and the stacking yard.
[0008] In ship unloading operations, quay cranes 11 access the
shipboard cargo containers from above the ship and move them to the
ground level or dockside cargo container transporters 21 such as
chassis trucks, trailer trucks, or automatically guided vehicles
(AGVs). The transporters deliver the containers to the stacking
yard 19 where other vehicles or cranes 23 transfer the containers
to stacks. In loading operations, quay cranes lift the cargo
containers from the dockside container transporters and move them
to the ship where they are lowered into shipboard cells. The
berthing operations involve three separate types of sub-operations:
(1) quay crane handling; (2) transport between the crane and the
stacking yard; and (3) storage yard manipulation.
[0009] Quay cranes in the form of cargo container handling gantry
cranes are arranged to extend over a longitudinal expanse and
transfer cargo containers horizontally from one deposition area to
another. The largest of such gantry cranes are primarily located
dockside in shipping ports around the world as well as in railroad
yards. Quay cranes generally have either a horizontal sliding boom
or a cantilever boom, the latter of which can usually be raised by
rotating it around its inboard end. Long span yard and quay cranes
are typically supported by vertical structures located inboard from
the ends of the crane gantry on rail mounted wheels. The present
invention can be utilized with any of these basic types of crane
designs and operations.
[0010] Reference is made to FIG. 2 of the drawings which illustrate
a typical cantilever boom type quay crane 11 having a buffer crane
25 of the present invention positioned thereunder. The quay crane
cantilevered rotatable boom 27 is supported by the crane
superstructure 29 mounted on crane truck wheels 31 which run on
dock rails which are disposed parallel to the edge 13 of the harbor
dock. The crane superstructure supports a horizontal gantry 33
disposed generally mid-height thereon at an elevated location above
the cargo container pickup and deposition areas 35. The gantry is
supported from below by the main legs of the superstructure.
[0011] In the cantilevered rotatable boom design for quay cranes,
sheaves are disposed at the pinnacle 37 of the superstructure of
the crane to guide wire rope reeving 39 which is used to lift the
outboard or cantilevered end of the boom to the upright raised
stowed position. The wire rope reeving raises the cantilevered boom
by rotating it about its hinge point 43 at its inboard end
proximate to the superstructure.
[0012] While, in most typical dockside applications, the gantry of
a cargo container handling quay crane is a slidable or a raisable
cantilevered boom extending from a crane superstructure to project
over a ship, other types of large gantry yard cranes supported at
both ends are located in large cargo container storage or transfer
areas. All of these cranes are similar to the gantry type crane of
FIG. 2 in that they employ a movable trolley 45, usually with a
suspended operator's cab 47, which shuttles along the gantry 33 and
boom 27 suspending a cargo container lifting spreader 49. The
spreader can be raised or lowered from the crane gantry by the
operator and engages from above the top of cargo containers 17. The
containers are carried by a transporter 21 or are stacked on the
dock or shipboard to permit them to be lifted by the trolley for
horizontal transport. During loading, the containers are lifted
from the transporter and are moved outboard along the gantry to
where they are lowered into the cells 51 in a cargo container
transport ship. During unloading, the containers are lifted from
the cells and moved from shipboard to shore where they are lowered
onto the transporters.
[0013] The cargo container lift trolley 45, mounted on rails on the
crane gantry sections 27, 33, can traverse from one end of the
gantry to the other with a suspended container. The cargo container
lifting spreader 49 is suspended from the trolley by fleet through
wire rope reeving through a detachable headblock which carries the
wire rope suspension sheaves. Different or variable length
spreaders can be secured to the headblock to accommodate
correspondingly different size containers.
[0014] There are two highly interdependent berthing sub-operations:
(1) quay crane handling; and (2) transport vehicle movements
between the crane and the stacking yard. A delay in one of those
sub-operations causes the other to pause and idle which reduces the
overall productivity of the entire system. Several factors can
cause delays in the two berthing sub-operations including: (1)
unsteady or irregular quay crane operations; (2) the time required
for effecting interbox connector (IBC) installation and removal
processes; (3) delays in stacking yard operations that delay
throughput of transport vehicles; (4) the time required for quay
cranes performing alignment of containers with transport chassis;
(5) congestion of transport vehicles under quay cranes; and (6)
various other factors such as machinery operator mistakes or
inexperience.
[0015] Quay crane container handling rates are measured in cycle
rates. Unsteady quay crane operations result because the cranes
move containers different distances depending upon the location of
the container on a ship varying the cycle rates. For example, as a
quay crane loads or unloads each column of containers spaced across
the beam of the ship, the hoist travels a longer distance outboard
for each successive column of containers and lowers and hoists
longer for each container located deeper in the stack. The
increased traveling distance and stationary time for the hoist, for
each successive container, adds to the container handling time and
the resulting cycle time.
[0016] Unsteady quay crane operation, coupled with a constant
number of transport vehicles allotted per crane, creates
inefficiencies in the overall operation. When quay crane handling
rates or cycle time are slow, transport vehicles must wait. In
those instances where the quay crane handles containers fast and
cycle time is short, and if the number of transport vehicles is
insufficient for the cycle time, the quay crane must wait.
[0017] The interbox connector (IBC) installation and removal
processes cause both quay cranes and transport vehicles to idle.
IBCs are cone-shaped devices that lock stacked containers together
on the ship. When quay cranes lift containers from the ship, the
IBCs are still attached to the bottom of the container. Usually,
the quay cranes must lower the container until it is a few feet
above the port terminal dock level where a worker crew can reach
underneath and remove the IBCs. The installation processes are just
the reverse. The IBC operations cause a significant amount of quay
crane and transport vehicle idle time to be induced into the system
cycle time as well as exposing the workers to the possibility of
injury from a swaying or dropped container or any other hazards
associated with proximity to a lifted load and to continuous
transport vehicle operations.
[0018] Delays in stacking yard operations also cause delays in the
throughput of container transport vehicles. The vehicles load or
unload containers at the stacking yard before returning to the
cranes. Disruptions in the flow of transport vehicles to and from
the quay crane loading area are caused by numerous factors such as
driver inexperience and lack of familiarity with the apparatus and
layout of the yard, as well as yard worker inexperience, which
cause the delays in the stacking yard operations. If the
disruptions are sufficiently severe, then the quay cranes must wait
in idle for a transport vehicle to return.
[0019] Another source of delay results when quay cranes expend time
aligning a suspended container with a container transport chassis
during the container positioning and deposition process. The
transport vehicles do not park in precise locations under the quay
cranes. As a result, each container placement is in a slightly
different location. This process of container lifting spreader
alignment with the transport vehicle causes time-consuming delay in
the quay cranes operation.
[0020] Finally, congestion of transport vehicles under the quay
crane slows the rate at which containers are moved to and from the
container ship. The situation is exacerbated when there are several
cranes working in parallel and the ship carries refrigerated
containers. The orientation of the refrigerated containers on the
ship often requires that vehicle traffic flow two ways under the
quay cranes in order to properly orient the containers on the
transport chassis whereas unidirectional flow would create less
congestion and danger to the dock workers.
[0021] The buffer crane operations and method of cargo container
handling contemplated according to the present invention departs
substantially from the conventional concepts, designs, and modes of
quay crane operation taught by the prior art. In doing so, the
present invention provides an apparatus and new method of
sub-operation primarily developed for the purpose of improving the
overall efficiency of berthing operations by reducing or
eliminating the delay problems described above. It accomplishes the
result in a different and improved manner and an overall new method
of operation for the dockside handling of cargo containers.
[0022] The buffer crane of the present invention functions mainly
by establishing a temporary storage or holding operation between
the quay cranes and the transport vehicles which reduces the
interdependence therebetween. The buffer operation in effect
constitutes a container reservoir between two of the three berthing
sub-operations: quay crane handling and transport between the crane
and the stacking yards. The temporary storage reservoir permits the
quay crane to take or deposit containers even if no transporter is
available, or conversely, for a transporter to extract a container,
or deposit one in the reservoir, even if the quay crane is
elsewhere. When one of the two sub-operations experiences a delay,
the other sub-operation continues to work with the buffer operation
while the delayed sub-operation resolves its problem.
SUMMARY OF THE INVENTION
[0023] In view of the foregoing known and obvious disadvantages
inherent in the prior art types of quay cranes and berthing
operations presently existing and utilized in seaports, the present
invention provides a new crane construction and method of quay
crane operation wherein the same can be utilized to improve the
efficiency of cargo container ship berthing operations.
[0024] The general purpose of the present invention, which will be
described hereafter in greater detail, is to provide a new crane
apparatus and method for coordinated quay crane operation which has
all of the advantages of the prior art mentioned above, as well as
many novel features that result in new methods of berthing
operations, which are not anticipated, rendered obvious, suggested,
or even implied by any of the prior art of quay cranes and port
berthing operations either alone or in any combination thereof.
[0025] The present invention is a buffer crane sub-operation for
cargo container handling. It is a method for dockside buffer crane
cargo container handling in combination with a quay crane. The
steps comprise providing an independently movable platform having a
multiplicity of cargo container landing positions disposed thereon
and a dedicated crane engaged with the platform arranged to move or
transfer containers between the platform and cargo container
transporters located below the platform. The platform is positioned
dockside under the quay crane and containers are moved by the quay
crane between the landing positions on the platform and shipboard
cells of a dockside berthed ship. Containers are also concurrently
moved by the dedicated crane between the platform and cargo
container transporters located below the platform.
[0026] These more important features of the method of the invention
have been broadly outlined in order that the detailed description
thereof which follows may be better understood and in order that
the present contribution to an improvement in the art may be better
appreciated. There are additional features of the method of the
invention that will be described hereinafter and which will form
supplemental subject matter of the claims appended hereto.
[0027] With respect to the claims hereof, and before describing at
least one preferred embodiment of the invention in detail, it is to
be understood that the invention is not to be limited in its
application to the details of construction and to the arrangements
of the components which are set forth in the following description
or illustrated in the drawings. The invention is capable of being
created in other embodiments and of being practiced and carried out
in various ways. Also, it is to be understood that the phraseology
and terminology employed here are for the purpose of description
and should not be regarded as limiting.
[0028] As such, those skilled in the art will appreciate that the
conception upon which this disclosure is based may readily be
utilized as a basis for the designing of other forms, structures,
methods, and systems for carrying out the several purposes of the
method of the present invention. It is important, therefore, that
the claims be regarded as including such equivalent steps in the
method in so far as they do not depart from the spirit and scope of
the present invention.
[0029] Further, the purpose of the appended abstract is to enable
the United States Patent and Trademark Office, and the public
generally, and especially scientists, engineers and practitioners
of the art who are not familiar with the patent and legal terms or
phraseology, to determine quickly from cursory inspection the
nature and essence of the technical disclosure of the application.
The abstract is neither intended to define the invention of the
specification, which is measured by the claims, nor is it intended
to be limiting as to the scope of the invention in any way.
OBJECTS OF THE INVENTION
[0030] It is therefore an important object of the present invention
to provide a new sub-operation for shipping port berthing
operations which provides a buffer operation between quay crane
operations and the container transport vehicles which service a
stacking yard.
[0031] It is another object of the present invention to provide a
buffer operation for quay crane berthing operations which provides
an intermediary landing deck forming a cargo container reservoir
between quay crane handling and dockside vehicle transport.
[0032] It is a further object of the present invention to provide a
buffer crane operation to work in conjunction with a quay crane to
increase the efficiency of berthing operations by reducing idle
time of the quay crane and container transport vehicles.
[0033] It is still another object of the present invention to
provide a new gantry frame apparatus for the sub-operation method
having a protected service deck for port operators to perform IBC
installation and removal operations while the containers are landed
on the buffer crane whereby neither the quay crane nor the
container transporters need to idle during those operations.
[0034] And it is yet a further object of the present invention to
provide a supplemental independently movable gantry crane which can
be supplied to presently existing quay cranes without additional
tracks on the dockside and which provides a landing deck for
containers and performs a supplemental buffer sub-operation to quay
crane operations and permits IBC removal independent of quay crane
involvement to increase the efficiency of berthing operations by
reducing the quay crane cargo container handling cycle times.
[0035] Other objects and advantages of the present invention will
become apparent when the method of the present invention is
considered in conjunction with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a schematic diagram in plan view of a ship
berthing operation and a cargo container stacking yard;
[0037] FIG. 2 is a side elevation of a typical quay crane with a
typical buffer jib crane of the present invention located
thereunder;
[0038] FIG. 3 is a is a perspective view of a typical buffer jib
crane of the present invention shown in operation; and
[0039] FIG. 4 is a perspective view of a cargo container
predetermined deposition position on the landing deck of a buffer
crane.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0040] Reference is made to the drawings for a description of a
preferred embodiment of the apparatus utilized for implementing the
method of the present invention wherein like reference numbers
represent like elements on corresponding views.
[0041] Reference is made to FIGS. 2 and 3 of the drawings which
show a quay crane 11 and a buffer jib crane 25 which are located
dockside in a shipping port. The buffer crane is low profile so
that it can be positioned underneath a quay crane during container
handling operations. It is contemplated that a buffer crane could
also be utilized in a railroad stacking yard as well as dockside
under a large bridge or straddle crane, so the term "quay crane" as
used in the claims is intended to include these types of cranes
also.
[0042] FIG. 3 shows the buffer jib crane in operation. It is
essentially a landing deck where containers can be landed and
temporarily stored by a quay crane when they are removed from
shipboard or where containers picked off ground level transporters
can be landed until they are picked up by the quay crane for
transport to a ship. The buffer jib crane is a gantry frame forming
a raised or elevated upper platform 53 with a subplatform 55. The
buffer crane sits under a quay crane and interposes a container
reservoir between the quay crane and the container transport
vehicles. The quay crane can take or extract containers therefrom
and the buffer crane can deliver containers therefrom to the
transporters. It creates a new and additional sub-operation in ship
berthing operations which reduces quay crane cycle time in cargo
container handling.
[0043] The quay crane 11 deposits containers 17 onto the top of the
buffer crane or retrieves them from the upper platform 53 called
the landing deck. A subplatform 55 disposed below the landing deck
is a working area for port operators called a service deck. The
landing deck can support multiple containers to function as the
container reservoir in the buffer operation. Container transport
vehicles 21, such as chassis trucks, trailer trucks, or AGVs, drive
alongside the raised platform to either deliver or receive
containers to and from the buffer crane landing deck. A dedicated
container handling crane 57 engaged with the buffer crane platform
moves the containers between the landing deck and the transport
vehicles.
[0044] Port operators can also perform certain tasks on the
containers from the safety of the service deck 55 while the
containers rest on the landing deck 53. With current methods of
operation, both the quay cranes and transport vehicles must sit
idle while the IBCs are installed or removed. The buffer crane
system allows port operators to perform IBC installation and
removal operations while the containers rest on the upper platform
so that neither the gantry cranes nor the transport systems need to
idle during the IBC attachment or removal process. In addition,
service personnel can verify container identification, re-mark a
container, or perform minor container servicing while it resides in
the buffer pool on the landing deck.
[0045] The upper platform or landing deck 53 has fore and aft and
lateral edges 59, 61, 63. In the preferred embodiment of the
present invention, both platforms 53, 55 are supported at the
lateral edges 63 thereof by four vertical support columns 65
disposed at the comers of the gantry and which are interconnected
at the lower ends thereof by two interconnecting sill beams 67.
Each sill beam connects the bottom of two vertical support columns
at the lateral edges of the crane and provides structure for the
gantry wheel drive area. The integral structure provides structural
support for the loads from the dedicated container crane 57, called
a slewing jib crane, for the buffer containers 17 deposited on the
landing deck 53, and for emergency impact situations and accidental
occurrences. The platforms are supported on pneumatic transport
wheels 69 for independent movement of the buffer crane 25.
[0046] The transport wheels 69 are secured to the sill beams 67
with a gantry drive for independent movement of the buffer crane 25
underneath the quay crane 11 and along dockside 13. The wheels are
rubber tires so that the crane can operate without tracks or rails
and can turn. Since the quay cranes move along the dock as they
unload each successive row of container cells along the length of
the ship, the buffer crane must likewise move along the dock to
remain positioned under the quay crane. The buffer crane gantry
drive is the arrangement of wheels, gear systems, drive motors, and
brakes that allow the entire buffer crane system to move. By
varying the speed of the tires, the crane can move in all
directions and is omni-directional. A majority of the time, the
wheels are aligned parallel to the edge of the dock which allows
the gantry frame of the buffer crane to move in the same direction
as the quay crane. In order to stay parallel with the quay crane,
the buffer crane performs small turns by varying the wheel speeds
on each side the crane.
[0047] As indicated earlier, the landing deck 53 of the buffer
crane stores containers 17 temporarily as a container reservoir or
pool thereby functioning as the essential buffer platform. The
landing deck is provided with at least one predetermined landing
position formed on the landing deck and has position guides to
receive and guide containers being lowered onto the landing
position. In the preferred embodiment of the invention, a multiple
of predetermined landing positions are dispersed over the landing
deck. The term "predetermined" means that they are specifically
located for automatic control of the crane operation. Generally
between two and five parallel landing positions will suffice for
the intended purpose of providing a container reservoir or pool.
Access to the containers is provided by the attached dedicated
independent cargo handling container crane in the form of a slewing
jib crane 57 as well as by the quay crane 11 from above. The
dedicated crane has container lifting apparatus 83 arranged to move
containers between the landing deck and the transporters located
alongside the platform.
[0048] The landing deck is wide enough to accommodate several
containers in the predetermined landing positions. Access to the
bottom of the containers deposited on the landing deck is provided
by openings 71 therein at the predetermined positions. Different
types of openings in the landing deck may be required depending
upon whether the IBC installation and removal operations are manual
or automated. Shock absorbing mechanisms diminish the force of the
continuous impacts which result from the container landing
operations as well as impacts which occur in emergency situations.
The pneumatic rubber tires 69 augment the shock absorbing
mechanisms. The landing deck protects workers who operate below, on
the service deck 55, from exposure to injury and inclement
weather.
[0049] Reference is made to FIG. 4 of the drawings which shows a
container landing position 71 on the landing deck 53. These
positions are defined by angular slides 73 that vertically guide
the containers into place during landing on the deck to simplify
the placement of the containers thereon. During lowering of the
containers onto the buffer platform, the bottom edges of the
containers engage the guides which stop residual container sway of
the suspended load and laterally displace the container into proper
alignment onto the respective deposition position. The descending
container slides downward along the guides in the vertical
direction. Therefore, the container landing process requires less
precision than current methods utilized with container transport
vehicles. This saves considerable time by reducing container
positioning requirements. It also reduces the work demand on the
quay crane operators who currently endure fatiguing conditions.
Essentially, much less time is spent on the placement of a
container because the quay cranes do not need to perform tedious
positioning adjustments. The guides also place the containers in
specific locations so that the jib crane may accurately move to the
predetermined deposition and pick-up positions above the landing
deck by automated control.
[0050] The slewing jib crane 57 shown in closer detail in FIG. 3 is
engaged with the upper platform 53 of the buffer crane 25 and moves
the cargo containers 17 between the landing deck 53 and the
transport vehicles 21. The jib crane is comprised of a slewing
armature 75 which is comprised of at least a pair of articulated
sub-armatures. A main first sub-armature 77 is pivoted on a support
post 79 and secured to one of the lateral edges of the landing
deck. The inboard end of the first sub-armature is pivoted on the
post for rotational movement in a horizontal plane around the post.
A second sub-armature 81 has its inboard end secured to the
outboard end of the first sub-armature and also is pivoted thereto
for rotational movement in a horizontal plane. The second armature
supports cargo container lifting apparatus 83 at the outboard end
thereof which can rotate more than 180 degrees.
[0051] The slewing armature is arranged to provide full
two-dimensional horizontal motion to each of the landing deck
container deposition positions, and the vehicles below, in order to
move or transfer cargo containers between the platform and cargo
container transporters located alongside and below the platform.
The term "below" includes positions at the sides of the gantry
frame at dock level either level with or below the landing and
service decks. It is possible that the transporters could travel
the dock at a level above the buffer crane landing deck and the
term "below" is intended to cover such a landscape, but there is no
known comparable situation.
[0052] The slewing jib crane 57 articulates by turning each
armature at each of three rotation points: the connection between
the support post 79 and the inboard end of the first sub-armature
77; the connection between the outboard end of the first
sub-armature and the inboard end of the second sub-armature 81; and
the connection between the outboard end of the second sub-armature
and the cargo container lifting apparatus. The second sub-armature
supports the cargo container lifting apparatus at its outboard free
end in the form of a lifting spreader suspension block 83 which can
rotate more than 180 degrees to turn a suspended lifting spreader
49 and attached cargo containers 17 end-for-end around a vertical
axis to reverse the longitudinal orientation thereof. The first and
second sub-armatures and the cargo container lifting apparatus are
mounted on the support post at a high enough level to permit the
lifting spreader suspended from the suspension block to pass above
cargo containers deposited on the landing deck at a level below the
supporting structure of any cargo container quay crane it is
positioned under.
[0053] The cargo container lifting apparatus operates by reeling in
and paying out rope from the suspension block 83 that suspends the
lifting spreader 49 whereby the apparatus is considered rope
driven. The lifting spreaders are mechanisms that engage and hold
containers while they are being lifted. Each corner of the spreader
has a twist lock to lock onto the container at the corner castings
thereof. The lifting spreader can be controlled by the crane
operator to reciprocate in the length of its engagement to a
container to accommodate different size containers in the lengths
of 20 feet, 40 feet, 45 feet, and two containers of 20 feet each,
linked end-to-end.
[0054] The cargo container lifting apparatus 49, 83, also has the
ability to perform incremental adjustments of the container's
position to facilitate alignment with the transport vehicles 21.
The apparatus accomplishes this result by giving and taking varying
amounts of slack in the suspension ropes. In this manner, the
apparatus can skew, list, and trim the container, as well as move
the container laterally and longitudinally. The lifting device
therefore can quickly position containers on transport vehicles
thereby eliminating the time-consuming task from the quay crane's
cycle time.
[0055] The buffer crane 25 includes an automated control system for
partial operation of the dedicated crane to position the cargo
container lifting apparatus over preselected positions on the
landing deck and to move containers with coordinated motion. The
slewing armature 57 moves automatically between predetermined
positions above the landing deck 53 to general positions above the
various transport vehicles 21. The crane operator only needs to
select from the alternative predetermined container deposition
positions on the landing deck to perform container engagement and
pickup from a position and for container deposition at a selected
position. Computer control performs precision alignment of the
cargo containers with respect to the landing deck positions and
general positioning of the container lifting spreader above the
container transporters. The buffer crane operator controls the
slewing armature for accurate alignment of the lifting spreader
with the transport vehicle for container pickup or deposition.
Computer software automatically controls the turning rates of the
three armature rotation points to insure that the movement is
smooth and linear during both operator and automatic control of the
slewing armature.
[0056] The slewing jib crane 57 helps reduce traffic congestion of
transport vehicles beneath the quay cranes 11 because it has the
ability to rotate containers about the vertical axis. When
refrigerated containers are handled, transport vehicles often need
to flow in opposite or two directions under the quay cranes to
accommodate for the different orientations of the refrigerated
containers coming off the ships. Because the slewing crane can
reorient the containers to correctly position them on a transport
chassis, the buffer crane system will allow traffic to flow in one
direction throughout the stacking yard and under the crane, thereby
reducing the amount of traffic congestion.
[0057] The service deck or work platform 55 is disposed below the
landing deck 53 to provide space for IBC attachment and removal
operations. As mentioned earlier, with current methods of
operation, both the quay cranes and transport vehicles must sit
idle while the IBCs are installed or removed. The quay cranes 11
must pause and hold the containers 17 a few feet off the ground so
that personnel can manually install or remove the IBCs. The
proximity of the personnel to the lifted container is also a safety
hazard. The landing deck 53 of the present invention covers the
service deck 55 so that the workers are never in a situation where
lifted loads are freely suspended overhead, as can occur in present
operations, which is an inherently dangerous situation. If the
height limitations for the buffer crane are restricted, it is
possible that the service deck cannot be located directly below the
landing deck. The situation may require a multiple of lowered
service decks disposed between the container deposition positions
on the landing deck for the service workers to operate from.
[0058] In the buffer crane system, the landing deck 53 covers the
service deck 55 so that the service worker personnel can install
and remove the IBCs from below through the openings 71 in the
landing deck 55 while the container rests safely on the upper
platform. This service deck provision of the buffer crane system
allows the safe and efficient installation and removal of the IBCs.
It provides port operators with a work area within which to remove
the IBCs from the cargo containers deposited on the landing deck
either by hand or with IBC removal machinery. Machines or robotics
can be provided to aid IBC installation and removal operations for
further reducing the strain and danger for worker personnel and
increasing the speed of quay crane operations. As a result, the
quay cranes and transport vehicles do not need to idle or wait
while the IBC installation or removal process occurs.
[0059] The buffer crane operator works in an operators' cabin 85.
It contains all the automotive and the slewing jib crane 57
controls. Logistics are included to help the operator communicate
with the quay crane operator and the service deck workers. Since
the operator must communicate with so many individuals, it is
essential that communication be clear and simplified to insure
safety and productivity. Signal lights on the landing deck
automatically indicate to the quay crane driver which containers
are to be loaded onto the ship or have already been unloaded. There
are indicator lights controlled by the service workers which tell
the buffer crane operator whether the IBCs have been removed or not
so that the operator does not prematurely move the container. The
operator cabin provides simplified controls for the crane driver by
reason of the computer controlled positioning of the slewing
armature at the predetermined deposition positions on the landing
deck.
[0060] A diesel engine which is coupled to an alternator provides
power to the buffer crane system. The engine and alternator couple
rests on one of the sill beams along with the fuel tanks. Weather
protected steel enclosures protect the diesel engine and alternator
couple from wear and possible damage.
[0061] During operation of the buffer crane, an electronic system
automatically aligns the buffer crane with the quay crane along the
cargo container transporter traffic lanes. The system can be
comprised of optical, radio, or ultrasonic devices to measure the
distance and relative position of the buffer crane to the quay
crane. Information is linked to the quay drive system
electronically which repositions the buffer crane until it is in
the correct position directly below the quay crane trolley track
and parallel to the quay crane quay wheels.
[0062] Another electronic system insures that there is no
interference or collision between the quay crane spreaders. With
two devices accessing the buffer platform, the quay crane and
slewing jib crane, there is potential for interference and
collision. The electronic system will identify the position of the
quay crane lifting spreader to ensure that this does not occur.
[0063] The buffer crane system has features that improve
productivity and safety of port operations. The buffer crane is a
stand-alone machine. It can operate with any existing quay cranes.
The quay cranes require only minimal modification to accommodate
the electronic linking systems. There are no costs involved which
would be due to required extensive crane modifications or crane
downtime. Because the buffer crane travels on rubber tires, the
buffer operation does not require tracks, so there is no need to
install additional rails on the port surface. The buffer crane has
the advantage that is easy and inexpensive to install and can be
applied to many cargo container handling ports in operation
today.
[0064] The present invention constitutes a method for dockside
buffer crane cargo container handling working in combination with a
quay crane. The method is a ship berthing sub-operation and
comprises several steps, the first of which is providing an
independently movable platform having a multiplicity of cargo
container landing positions disposed thereon. The movable platform
has a dedicated crane engaged therewith which is arranged to move
containers between the platform and cargo container transporters
located below the platform. The platform is positioned on the
dockside under the quay crane.
[0065] Cargo containers are moved by the quay crane between the
landing positions on the platform and shipboard cells of a dockside
berthed ship. Cargo containers are also moved by the dedicated
crane between the platform and cargo container transporters located
below the platform concurrently with the movement of containers by
the quay crane. The term "concurrently" means that both cranes can
be operating and moving containers at the same time. It is only
that period of time when the quay crane is depositing or retrieving
containers from the platform that the dedicated crane must remain
clear of the platform. The dedicated crane can be operating to
deposit or remove a container with respect to a transport vehicle,
but the automatic controls of the crane prevent it from
mechanically interfering with the quay crane.
[0066] The method of the present invention includes the separate
step of performing interbox connector installation and removal
operations while containers are temporarily positioned on the
platform.
[0067] The method of the present invention also includes the
separate step of independently moving the platform to each
operational position of the quay crane on the dock as the quay
crane moves along said dock to unload the length of a container
ship.
[0068] The method of the present invention also includes the
separate steps of utilizing three different types of dedicated
buffer cranes: (1) a slewing jib crane; (2) a bridge crane; and (3)
a straddle crane.
[0069] The method for dockside buffer crane cargo container
handling in combination with a quay crane therefore resolves many
of the delay issues described earlier. Even when one of the
sub-operations of quay crane handling or container dockside
transport is delayed, the other sub-operation may continue by
accessing the containers on the buffer platform. The delayed sub
operation can address the delay, and the other crane continue its
work. The complete elimination of IBC installation and removal
operations from the quay crane cycle time provides a huge
improvement in the efficiency of berthing operations.
[0070] In summary, the buffer crane system improves productivity
and efficiency of port operations by providing a buffer operation
between the quay cranes and transport vehicles sub-operations. This
buffer allows quay cranes and vehicles to operate independently so
that delays in one sub operation do not slow the overall
productivity. Additionally, the buffer allows port operators to
perform tasks on containers such as marking and inspection while
they sit on the buffer platform rather than having the quay cranes
and transport vehicles wait while those operations are
performed.
[0071] Thus, it will be apparent from the foregoing description of
the invention in its preferred form that it will fulfill all the
objects and advantages attributable thereto. While it is
illustrated and described in considerable detail herein, the
invention is not to be limited to such details as have been set
forth except as may be necessitated by the appended claims.
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